如何聲明一個包含多個整數值的變量SQL Server

Question

我想將某些ID存儲在變量中，然後在查詢中必須使用該變量多次。我用這個格式：

DECLARE @aid INT 
SELECT @aid = AP.aid 
FROM 
    sub_aminer_paper AP 
GROUP BY 
    AP.aid 
HAVING 
    MIN(p_year) = 1990 AND MAX(AP.p_year) = 2014 AND COUNT(AP.pid) BETWEEN 10 AND 40 

SELECT 
    * 
FROM 
    sub_aminer_paper 
WHERE 
    aid = @aid 

但是，這給我的結果只從ID的列表任何一個ID爲我所用的查詢從表sub_aminer_paper檢索多個ID的。

請幫助和謝謝！

Answer 1

你想要的是一個table variable：

DECLARE @aid TABLE(id INT PRIMARY KEY) 

INSERT INTO @aid 
SELECT AP.aid 
FROM sub_aminer_paper AP 
GROUP BY AP.aid 
HAVING 
    MIN(p_year) = 1990 
    AND MAX(AP.p_year) = 2014 
    AND COUNT(AP.pid) BETWEEN 10 AND 40 

SELECT * 
FROM sub_aminer_paper 
WHERE 
    aid = (SELECT id FROM @aid) 

Answer 2

你也可以做到這一點，而無需使用一個變量，像這樣的東西：

SELECT * 
FROM sub_aminer_paper AP1 
where exists (
    SELECT 1 
    FROM sub_aminer_paper AP2 
    WHERE AP1.aid = AP2.aid 
    GROUP BY AP2.aid 
    HAVING 
    MIN(AP2.p_year) = 1990 
    AND MAX(AP2.p_year) = 2014 
    AND COUNT(AP2.pid) BETWEEN 10 AND 40)